Factory Mast LS1 - Cathedral - Gen III & IV Cylinder Heads

243/799/317 Factory Ported Cylinder Heads

Priced Per Pair of Heads - allow minimum 4 weeks for shipping

No Core

Factory Mast ported GM cathedral porting service is a great option for those looking for great bang for your buck. These ports are now available to you in our Factory Mast cylinder heads.

Specifications: GM Stock LS Cathedral

• Stock Chamber (65cc)
• Intake Port Volume 223 cc
• Exhaust Port Volume 83 cc
• CNC porting
• Seats: Stock Iron
• Guides: CHE Bronze  Guides 8mm Stock Valve
• Minimum Bore: 3.890"

All Factory Mast Heads get:

• Teardown | Clean | Inspect
• 5-Axis CNC Porting
• Precision CNC Valve Job
• Recondition/clean all gasket surfaces and ends
• Hand Blending
• Surfacing
• Final Wash and Assembly
• Pressure Tested

Flow:

Intake 

0.100 - 66 cfm

0.200 - 141cfm

0.300 - 209 cfm

0.400 - 257 cfm

0.500 - 295 cfm

0.600 - 305 cfm 

0.700 - 307 cfm

Exhaust 

0.100 - 51 cfm

0.200 - 107 cfm

0.300 - 154 cfm

0.400 - 186 cfm

0.500 - 210 cfm

0.600 - 223 cfm

0.700 - 229 cfm